You do get credit though - email Farsight support about it and give them your kickstarter username so they can look it up.
I think it's good for one table pack or something.
I might be misunderstanding. For someone like me who supported the Kickstarter, I obviously the kind of person who will buy all the Season passes, so therefore how would I use a table pack credit? Maybe it can be used for a discount?
If you backed a table via Kickstarter and selected PC as your platform in the survey, you should get that table for free once you log into your Farsight account in the Steam version of the game. It worked for me. If you've done all that and not gotten your table, email Farsight.
That aside, I think the OP was trying to get at getting a discount on a season pass, seeing as a table they got for free is part of the season. I don't think Farsight is obligated to do anything like that. Plus, even if you account for the prices of the Kickstarted tables, I think the season pass is still a deal over buying them all individually.
Plus I think most people who did the Kickstarters are just glad to see the tables get made.